As used herein, the term “unmanned air vehicle” (“UAV”) refers to any unmanned object that can be gun launched, rocket launched, dropped from a vehicle that is already aloft, or otherwise made to fly through the air over great distances, such as rockets, missiles, projectiles, or any other like un-manned devices. A UAV may or may not include internal propulsion mechanisms. Thus, a UAV may include any un-manned object that can be made to fly through the air.
In general, it is desirable to increase the distance over which a UAV can be delivered and to decrease its delivery time. Unfortunately, UAV range and time for delivery have been limited by, among other things, low aerodynamic efficiency. Low aerodynamic efficiency may be characterized, for example, by a low Lift/Drag (“L/D”)) ratio and/or by the low aerodynamic drag of the UAV. It is also desirable to also increase the size and/or weight of the payload of the UAV. The payload is defined herein to be any material, ordinance, equipment or the like that is contained within or transported by the UAV. As further described below, UAV payload size has also been limited due to the bulk of the devices used to aid in the long range delivery of the UAVs.
An ongoing effort exists to develop a new apparatus and methods for extending the range of ordinance and other UAVs. For example, several attempts have been made to extend the range of projectiles, rockets, and the like regardless of the firing or launching device. In one example, such attempts involve projectiles that can be fired from guns. For example, the Forward Air Support Munition (FASM) concept involves a gun launched projectile that eventually deploys a parachute in order to deploy inflatable fixed wings, and then starts a diesel engine to cruise under remote control. The Gun Launched Observation Vehicle (GLOV) is launched from a Naval ship gun; GLOV also deploys an inflatable wing. The Wide Area Surveillance Projectile (WASP) is another gun launched projectile using a parachute for deceleration. After the WASP deploys its parachute, it unfolds a wing from the body and activates a propeller for cruising reconnaissance. Others, such as the EX-171 Extended Range Guided Munition (ERGM) are initially fired from a gun, but also include a rocket for additional range assistance. The Chance Vaught BGM-110 is a cruise missile with a rocket propulsion device and a deployable wing. The deployable wing is contained within the rocket body.
These approaches may have several drawbacks. For example, inclusion of a propulsion device (rocket, propeller, or the like) and the fuel to drive the propulsion device decreases the size and weight of the payload that can be carried by the UAV (assuming constant weight and size constraints). Similarly, the un-deployed wings occupy space within the body of the UAV that could otherwise be used for payload.
Furthermore, each of these devices exhibit various degrees of low aerodynamic efficiency, thus limiting the range of delivery of the payload or the range for a surveillance mission or the like. Moreover, no UAVs have been designed that can be configured to achieve high aerodynamic efficiency at all speeds (including supersonic, transonic, and subsonic) and/or at all altitudes. Previous UAV designs are so limited, for example, because the wings are fixed in a single deployed position. In a further example, on the Tomahawk Missile, the wings just pop out from the body mid-section to a full open position. Thus, no UAV's have any mechanisms for increasing range and/or reducing flight times by achieving high aerodynamic efficiency at all speeds. In addition, UAV designs that use a parachute are limited because the wings generally are only deployed once the UAV reaches relatively slower speeds. Thus, UAVs employing parachutes must lose much of their initial inertia as well as valuable time during deployment of the wing.